| Oenothera pennellii Munz, 1939 |
| Oenothera platanorum P.H. Raven & D.R. Parn., 1970 |
| Oenothera podocarpa (Wooton & Standl.) Krakos & W.L. Wagner, 2013 |
| Oenothera primiveris A. Gray, 1853 |
| Oenothera psychrophila Ball, 1885 |
| Oenothera pubescens Willd. ex Spreng., 1825 |
| Oenothera purpurea Curtis, 1796 |
| Oenothera purpusii Munz, 1932 |
| Oenothera refracta S. Watson, 1882 |
| Oenothera resicum Benavides, Kuethe, Ortiz-Alcaráz & León de la Luz, 2019 |
| Oenothera riskindii W.L. Wagner, 2005 |
| Oenothera rosea L'Hér. ex Aiton, 1789 |
| Oenothera rubra Cav., 1797 |
| Oenothera sceptrostigma Brandegee, 1889 |
| Oenothera serrulata Nutt., 1818 |
| Oenothera sinuata L., 1771 |
| Oenothera sinuosa W.L. Wagner & Hoch, 2007 |
| Oenothera speciosa Nutt., 1821 |
| Oenothera stubbei W. Dietr., P.H. Raven & W.L. Wagner, 1985 |
| Oenothera suffrutescens (Ser.) W.L. Wagner & Hoch, 2007 |